A large proportion of the population with hypertension remains undiagnosed, untreated, or inadequately treated, contributing to the rising burden of cardiovascular diseases in South Africa. A workplace may either mitigate or accentuate the risk factors for hypertension. A cross sectional study was conducted to determine the prevalence of undiagnosed hypertension and associated factors among 312 employees in a Logistics Company, South Africa. A modified, validated, self-administered WHO STEPwise questionnaire was used to collect data on demography, lifestyle factors, anthropometry and blood pressure (BP). Hypertension was defined at BP ≥ 140/90 mmHg. Data was analysed using STATA 14. Mean age of employees was 40 ± 10 years, with a 50% prevalence of undiagnosed hypertension. No significant association was observed between occupation and undiagnosed hypertension, except for high prevalence of undiagnosed hypertension among truck drivers and van assistants (43%), and general workers (27%), having higher odds of increased waist-to-height ratio. Hypertension was associated with age (OR = 2.3, 95%CI; 1.21–4.27), alcohol use (AOR = 1.8, 95%CI; 1.05–2.93), waist circumference (AOR = 2.3, 95%CI; 1.29–4.07) and waist-to-height-ratio (AOR = 3.7, 95%CI; 1.85–7.30). Improved and effective workplace health programs and policies are necessary for management of undiagnosed hypertension among employees. Longitudinal studies on mediation of occupation in association of demographic and lifestyle factors with hypertension in workplaces are needed.